Preparation Of Metal-doped Graphite Carbon Nitrede And The Application In Photo-assisted Catalysis Degradation

In recent years,photocatalysts have gradually become a popular research direction in the field of materials because of their extremely high selectivity and high activity in many reactions.This has also attracted the attention of a large number of researchers.Among them,graphitic carbon nitride（g-C₃N₄）has excellent properties such as easy synthesis,high stability,excellent electronic band structure,and rich content of synthetic elements,so it can be used as an excellent matrix to support metal atoms.In this study,a simple one-pot method and ionic preloading were used to prepare Fe-SA-g-C₃N₄,Co-C₃N₄,and Fe/Mn-C₃N₄ photocatalysts by preparing Fe,Co,and Mn atoms on g-C₃N₄.The three materials were characterized by X-ray photoelectron spectroscopy（XPS）,transmission electron microscope（TEM）,electron spin resonance spectrometer（ESR）,and scanning electron microscope（SEM）.Acetamiprid（ACE）and bisphenol A（BPA）were selected as the target pollutants.The degradation performance of the three photocatalysts under visible light irradiation was investigated.The main content of the study consists of the following three parts:（1）Study on the degradation of acetamiprid by Fe-SA-g-C₃N₄ activated hydrogen peroxide under visible lightIn this study,xanthine,cyanuric acid and melamine dispersions prepared by the reaction of carbon nitride precursor in an aqueous solution,then calcined to obtain a carbon nitride in a tube furnace.Meanwhile,before the ferric chloride was dissolved in carbon nitride body,a tube furnace in calcining prepared Fe-SA-g-C₃N₄ under the same conditions.Under visible light,contrast before and after activation through g-C₃N₄ and Fe-SA-g-C₃N₄ supported metal removing hydrogen peroxide acetamiprid effect.It found that under visible light,Fe-SA-g-C₃N₄ supported metal catalyst after the activation of the hydrogen peroxide degradation acetamiprid significant effect.Degradation optimum conditions a pH of 3.0,H₂O₂ concentration of 5 mM,the concentration of catalyst was 0.2 g/L,concentration of degradation case of 20mg/L acetamiprid need 20min,and excellent in cycle characteristics.（2）Co-C₃N₄ combined with visible light activated PMS to degrade bisphenol AIn this experiment,polyethyleneimine,melamine,and melamine were used as raw materials for the synthesis of carbon nitride,and vitamin B12 was used to modify them to calcine in a tube furnace to obtain Co-C₃N₄.Under visible light,continue to study g-C₃N₄ and Co-C₃N₄ two catalysts activated by potassium persulfate（PMS）to degrade the pollutant bisphenol A.Compared to dye pollutants,the degradation of bisphenol A is much more difficult,so the more active PMS is selected here to generate active free radicals.It is found that whether the pH of the solution is acidic or alkaline,Co-C₃N₄has excellent catalytic effect on the degradation of bisphenol A by PMS with visible light.Among them,PMS concentration was 0.4 g/L and catalyst concentration was 0.1g/L under optimal conditions.It only required 10 minutes to degrade bisphenol A at20 mg/L,and the cycle performance was excellent.（3）Fe/Mn-C₃N₄ photo-assisted PMS degradation of bisphenol AIn this experiment,polyethyleneimine,melamine,and melamine were used as raw materials for the synthesis of carbon nitride,and modified with hemin and four p-carboxyphenylporphyrin manganese in a tube furnace to obtain Fe/Mn-C₃N₄.Fe/Mn-C₃N₄ combined with visible light catalyzed PMS activation to produce active free radical degradation of bisphenol A.The experiment found that whether the pH of the solution is acidic or alkaline,Fe/Mn-C₃N₄ has excellent catalytic effect on the degradation of bisphenol A by PMS under the assistance of visible light.When the concentration of PMS is 0.2 g/L,the degradation concentration is 30 mg/L.BPA requires 10 minutes and its cycle performance is excellent.